Yes, you can get infected via a USB cable. There are documented cases of people plugging their phones into USB charging stations in public and they are getting infected. This is called "Juice Jacking" and is a real cyberattack. It can be used for either data theft or malware installation. Here's a link to an article written Nov 27, 2019, on FCC.GOV: 'Juice Jacking': The Dangers of Public USB Charging Stations

Additionally, it depends on whether you use your phone simply as a network connection or if your device is mounted as a storage device. In case of the latter, you can not only be infected, but in case of a cryptolocker virus, your phone could be totally destroyed (at least the data on it). This could also include things like a Dropbox account, if it is connected to your device.

He is a teenager and Tor Browsers are terrible. I had to keep cleaning a nephew's computer because of Tor. I explained it to him, but he kept doing it to get "free" music and "early release" games. Ugh!

Finally, as our devices get smarter, more holes are opened up for attackers to use. Personally, I would never willingly open myself up, especially when it is someone I know is re-offender. I love my nephews ... but ... nope!

My nephew is about 16 years old. Just like me at his age... He thinks he knows everything.

As it is my nephew... I honestly don't care if for one hour he was watching YouTube videos.

Worse case scenario?

Just let the father politely explain to his son the difference of COST of data roaming compared to a monthly plan by their ISP (surfing on a home Wi-Fi)

I am understanding when it comes to teenagers, though up to a point.

What I honestly do NOT like about teenagers is that by accessing adult content or even being "smart" and downloading "Tor Browser" thinking that they can "anonymously" and "securely" get access to various websites...

They not only put their own device at risk...

They put their parents devices at risk (which share the same router of course).

I know of a case where a laptop using Windows 10 got compromised as someone sharing the same home Wi-Fi was up to "no good"...Guess who the culprit was? The teenage son of a friend of mine using Tor Browser...He now "hates" me as his father asked him to hand over ALL of his devices and... I happened to notice a shortcut of "Tor Browser" on his laptop.

All I had to do then was ask: Why download Tor Browser?Then of course he had to "come clean" and show us his entire collection of illegally downloaded material (adult content included of course)*

I have not though heard of a single case of an Android phone getting infected / compromised by USB Tethering...

So thank you very much Don.W !

Edit: I also found out that his Internet Security software... was a cracked version... I am pretty sure THAT was the real culprit...

In my personal experience connecting my Samsung S7 to a PC, I am asked if the connection is charge only, hotspot, or storage access. So there is some protection there. If inadvertently connected as storage device then your at risk for infection from the host machine, assuming there is a infection present.

Since about Android 5 or 6, usb tethering and wifi hotspots are created and treated the same - as an internal VPN connection on the phone, between the cell modem and the (USB port or wifi radio) . This is why the tethered device doesn't see the phone through the tether connection.

This is also why you cant use a VPN app from your phone and use tethering or hotspots at the same time. Android only allows 1 VPN connection to be established on the phone at a time.

Yes, you can get infected via a USB cable. There are documented cases of people plugging their phones into USB charging stations in public and they are getting infected. This is called "Juice Jacking" and is a real cyberattack. It can be used for either data theft or malware installation. Here's a link to an article written Nov 27, 2019, on FCC.GOV: 'Juice Jacking': The Dangers of Public USB Charging Stations

Additionally, it depends on whether you use your phone simply as a network connection or if your device is mounted as a storage device. In case of the latter, you can not only be infected, but in case of a cryptolocker virus, your phone could be totally destroyed (at least the data on it). This could also include things like a Dropbox account, if it is connected to your device.

He is a teenager and Tor Browsers are terrible. I had to keep cleaning a nephew's computer because of Tor. I explained it to him, but he kept doing it to get "free" music and "early release" games. Ugh!

Finally, as our devices get smarter, more holes are opened up for attackers to use. Personally, I would never willingly open myself up, especially when it is someone I know is re-offender. I love my nephews ... but ... nope!